Fake Gallien Krueger 410T cab?

AndyVicus · #1 07-11-2011, 05:44 AM

Hi, I did buy a GK 410T cab and the laber upper the connector say "Impedance 4Ohm". I play with it about 2 or 3 time and I notice that with 300watt amp the sound pressure is poor. So I mesaures the total resistance of the cab and the meter say 12.3Ohm. So I think that some cone fail but all 4 cone is fully working. On the cone there isn't any label, only some number.
In your opinion can I ask to GK some incofrmation about the cone?

DWBass · #2 07-11-2011, 05:48 AM

Was the cab used when you bought it or new? If used, maybe the previous owner rewired it incorrectly. Are you sure all 4 speakers are working?

AndyVicus · #3 07-11-2011, 06:02 AM

Used of course. The ohm meter sey that all is working.
There isn't any reason for rewire the cab from pure parallel to parallel-series. I thij that the old owner for some reason did broke the cone and replace it witout any rule. But I have to be sure of this.

craig.p · #4 07-11-2011, 06:09 AM

Hm. That meter reading suggests (suspiciously) four 32-ohm drivers wired in parallel. A 300W solid state amp would be able to deliver only a small fraction of its power into that load. A 300W tube amp would be at serious risk of damage due to the impedance mismatch. I would pull all four drivers, measure each one with your meter, get the numbers off the magnets and baskets, check the wiring as DW said, etc. etc. etc.

EDIT: Andy, just saw your update. Never mind about pulling the drivers. Sounds like you already have. But check the resistance of each driver individually.

craig.p · #5 07-11-2011, 06:27 AM

Whoa, just thought of something else. Does this cab have a (ugh...) tweeter? If so, you can check whether it's wired in right. And if there's a true crossover, rather than just a series cap and/or resistor, then that's worth checking out, too. Sorry, not really familiar with GK cabs but there are certain things you can check out regardless of a cabs design.

AndyVicus · #6 07-11-2011, 07:02 AM

About 12 Ohm for every driver so the nominal impedance is 16Ohm. The total resistence are about 12 ohm in fact the speaker are wired in series-parallel.
On the rear the number are 165-5 and on the basket
082-0041
1098249

AndyVicus · #7 07-11-2011, 07:11 AM

No twetter and no crossover.

craig.p · #8 07-11-2011, 08:51 AM

Andy, is your ohmmeter zeroed? Sounds like you know what you're doing, but I figured I'd ask anyway.

If those things really are twelve ohms, I agree w/ you on what the nominal impedance probably is. Maybe that cab was wired series-parallel because he was using four of them (i.e. four identical cabs) and needed a four ohm total impedance. If your amp can do four ohms, wire those things up in parallel and you should be good to go.

AndyVicus · #9 07-11-2011, 09:31 AM

Yes, I know what I do. The mesaure is correct.
I did buy the cab and the amp, an GK 800RB, and I think that he don't need an higher impedence.

The problem is that he substitute the cone with cheaper and unknow cone that don't work well with the cab volume and reflex port. I'll try to contact GK directly and hope for an answere. The amp can drive a 4ohm cab.

PS: I'm sorry for my bad english.

craig.p · #10 07-11-2011, 10:01 AM

Ok, Andy, but while you're waiting, try connecting them all in parallel for 4 ohms. Even if the "unknown" drivers aren't well-matched to the cab design, they may be close enough to allow you to EQ around the problem.

Yes, your 800 wants 4 ohms for full output. Into 16, you're probably not making much more than 125-150 watts.

You're using the correct speaker output, and NOT enabling the biamp feature, right?

When contacting GK, forget about emailing. I never got a reply about my defective MB200, even after two tries. Call instead (though I know it may cost you money from where you are).

Your English is fine. No apology necessary.

AndyVicus · #11 07-12-2011, 12:07 AM

The amp can deliver only 300W on a 4Ohm load, 200W on 8Ohm. I read that GK use Paragon driver and the product code is similar to mine. Something like "082-00xx", I don't found official data, probabily the age of the cab is the reason.

AndyVicus · #12 07-12-2011, 06:32 AM

Tha old owner say me that he did buy the cabinet and didn't substitute/modify it. He did sell me it as he did buy. It's possible that GK did a mistake about wiring?

I try to contact Eminence and they response is that they start build driver for GK only some year ago.
I try also to contact GK by email without response. I'm not able to take a phone conversation.

banikek · #13 07-12-2011, 07:39 AM

I own two of the GK 410T cabinets. Both are 100% stock and sound great. They are both 8 ohm cabs.

craig.p · #14 07-12-2011, 07:53 AM

Quote:

Originally Posted by AndyVicus

I'm not able to take a phone conversation.

What about Skype?

AndyVicus · #15 07-12-2011, 08:07 AM

Quote:

Originally Posted by craig.p

What about Skype?

In sens of ability to speak english at phone.

AndyVicus · #16 07-12-2011, 08:10 AM

Quote:

Originally Posted by banikek

I own two of the GK 410T cabinets. Both are 100% stock and sound great. They are both 8 ohm cabs.

Another strange things. My cab is labeled 4Ohm and in the same label there is the serial number. With 16Ohm driver is not possible to have a 8Ohm cabinet.

AndyVicus · #17 07-12-2011, 09:16 AM

Ok, GK technician say that the driver is correct.